Piston.



E. T. ROBINSON.

PISTON.

APPLICATION FILED DEC. 30, 1910.

1 Q3 510 Patented Sept. 10,1912.

mile/ 1830:?

NITED STATES PATENT OFFICE.

v EARL-E '1. ROBINSON, 015 UNIVERSITY, MISSOURI, ASSIGRQR To .ROBINSON FIRE APP-L- RA'IUS MANUFACTURING COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION O MISSOURI.

Specification of Letters Patent." Patented Sept. 1912.

Application filed December 30, 1910. Serial No. 600,018.

One of the objects of the present invention is to provide improved means whereb the packing-expanding means may be locke to hold the packing in its expanded position. I I

Other and further objects will appear in the specification and be specifically pointed out in the appended claims, reference being had to the accompanying drawings exemplifying the invention in its application to Y away and parts shown in section.

a gas engine piston In the drawings Figure 1 is a top plan View of a piston embodying the features of the present invention, parts being lipokeg 1g. is an axial section of the same, parts being shown in elevation.

Referring more articularly to the drawings and to theem odiment shown therein, the. piston head comprises a heavy end portion or plate 1 to which is secured a cup leather 2 by means of screws 3. Said piston has integrally constructed therein an upwardly contracted annular shell 4 from the inner cylindrical wall of which adjacent the end portion 1, project a pair of integral rodpin bearing lugs or bosses 5 for receivm the. pin 6. For this urpose, the bosses are provided with ournal bearings, as shown, the circular hole in the right hand boss 5 being extended through to the outside of the piston head to permit the pin 6 to be-introduced endwise therethrough into position. As shown in the drawings, the rod end 7 of a connecting rod 8 is journaled.

' j wedging shoulder 9, which is provided between the solid end 1 and the contracted portion of the piston head, coo erates with f a wedging and spacing rin 10 or the paokllllg, said ring 10 be1ng s idably mounted upon the, outer cylindrical wall of said c0ntracted portion of the piston head. Interposed between the shoulder 9 and the wedglnlg rmg 10 are a pair of packing rings 11, w ile between the' wedgin ring 10 and a follower or compressing ring 12 are interposed packing rings 13.

In order to provide means for'moving the follower or compressing ring 12 along the outer wall of the contracted portion 4 so as to compress the rings 11 and 13 to expand them circumferentially, the up er contracted portlon 4 of the piston head 1s threaded to receive a threaded ring 14 which, when turned on its axis. in one direction moves the follower or compressing ring 12 toward the solid end 1 of the piston, thereby expanding the piston rings 11 and 13 circumferent-ially. As preferably constructed, the upper annular edge of the threaded rin 14 1s beaded at 15, said bead 15 being rovlded 16, which may be used for the reception of a wrench of any suitable construction for turning the ring 14.

threaded ring 14 in any desired position, to prevent it from worklng loose and so defeating the ends of its em loyment, a spring latch 17-, which ma be rlgidly mounted on the inner wall of t e contracted portion 4, has a radiall projecting nose 18 which is resiliently he (1 in engagement with any one of a series of notches 16. Said latch is also provided with an upwardly projecting lug or finger hold 19 whereby the nose 18 mav be drawn out of the notch within which it is seated to permit an adjustment of the ring 14. The ad ustin ring 14 is thus releasably held against disp acement and so prevents axial movement of the follower or compress,

here, while at the same time the spacing ring 10 and the wedging shoulder 9 provide a. similar pair of wedging members, which members are adapted to bring about a circumferential enlargement of the-packing.

a pair of oppositelyisposed wedging mem-- with a plurality of radially dispose notches In order to provide means for locking the said contracted Having thus described my invention, the following is what I claim as new therein,

and desire to secure by- Letters Patent:

1. In a piston, the combination of apiston head having a rearwardly contractedposed about'said contracted portion adjacent said beveled shoulder, and a member slidable axially on said contracted portion and provided with a beveled shoulder adapted to cooperate with the first said beveled shoulder to expand the packing radially by its axial movement.

3. In a piston, the combination of a piston head having a rearwardly extending contractedpoition and a beveled shoulder at the forward end of said contracted portion, a follower ring slidable axially along said contracted portion and having a beveled shoulder adapted to coiiperate with the first said beveled shoulder, packing disposed between said beveled shoulders, and means threaded to 'said contracted portion for moving said follower ring. I

4. In a piston, the combination of a piston head having a rearwardly extending con tracted portion and a beveled shoulder at the forward end of said contracted portion, a follower ring slidable axially along said contracted portion, and having a beveled shoulder adapted tocooperate with the first said beveled shoulder, packing disposed between said beveled shoulders, means threaded to said contracted portion for moving said follower ring, and means releasably engaging said threaded means to hold it against rotation.

5. In a piston, a piston head having a contracted rear portion, packing surrounding said contracted rear portion, a packing ex pansion follower also surrounding said contracted rear portion, a ring threaded to said contracted rear portion, and a ring abutting said follower to operate the latter.

6. In a piston, a piston head having a contracted rear portion packing surrounding said contracted rear portion, a packing expansion follower also surrounding said contracted rear portion, a ring threaded to said contracted rear portion, and means for the ring for adjusting said packing having notches in its upper edge, and a locking device carried by the piston head and adapted to engage said notches to lock the ring in adjusted position.

9. In a iston, the combination of a piston head having a rearwardly projecting portion, said head. being provided with a beveled shoulder adjoining said contracted portion, a follower ring slidable axially along said contracted portion and having a beveled shoulder cooperatively disposed with respect to the first said beveled shdiil? der, a wedging ring slidable on said contracted portion intermediately of said beveled shoulders, said wedging ring being provided with bevels on opposite sides, packing rings disposed between said wedging ring and each of said beveled shoulders, respectively, and means for forcing said follower ring toward said pand the packing rings.

piston I head to ex 7 10. In a'piston, the combination of a piston head having a rearwardly projecting portion, said head being provided with a beveled shoulder adjoining said contracted portion, a follower ring slidable axially along said contracted portion and having a beveled shoulder. cooperatively disposed with respect to the first said beveled shoulder, awedging ring slidable on said contracted portion intermediately of said beveled shoulders, said wedging ring being provided with bevels on opposite sides, packing rings disposed between said wedgmg ring and each of said beveled shoulders, respectively, and means for forcing said follower ring toward said piston head to expand the packing rings, said means comprising a ring threaded to said contracted portion and having notches in its outer edge and a spring latch secured to said contracted portion and releasably engaging in said notches.

J. B. MEGowN, M. C. HAMMON. 

